Ablative Radioembolization for Hepatocellular Carcinoma Supplied by the Inferior Phrenic Artery

This single-center retrospective study included 43 patients with HCC treated with radioembolization via the IPA between January 2017 and December 2023. Inclusion criteria consist of BCLC A or B, tumor size 4 ~ 12cm, tumor number 1 ~ 3, and the primary target tumor supplied by the IPA. Treatment through the IPA and the hepatic artery was performed in the same session. The prescribed radiation activity via the IPA and the hepatic arteries were calculated using the single-compartment medical internal radiation dosimetry (MIRD) model, and the multi-compartment model, respectively. Local tumor progression-free survival for the primary index tumor, progression-free survival, and overall survival were evaluated by Kaplan–Meier curves.

Results:

43 patients were treated with glass (n = 27) or resin (n = 16) microspheres. Radiation activity infused via the IPA ranged from 0.05 GBq to 2.84 GBq (mean 0.50 ± 0.50 GBq, median 0.39 GBq). Total radiation activity infused via the IPA and hepatic artery ranged from 1.79 GBq to 11.75 GBq (mean 4.47 ± 1.89 GBq, median 4.13 GBq). According to the retrospective multi-compartment post-treatment dosimetry with PET/CT, the TNR and ADT were 5.0 ± 2.7 (range 1.5 ~ 13.7, median 4.5), and 629 ± 393 Gy (range 125 ~ 2325 Gy, median 527 Gy). The best tumor response were CR in 19 patients (44.2%), partial response in 23 patients (53.5%), and stable disease in 1 (2.3%). The 2-year and 5-year overall survival rates were 88.5% and 77.0%, respectively. Median local tumor progression-free survival was 32.0 months (95% CI, 15.0 ~ 49.0 months), and median progression-free survival was 14.8 months (95% CI, 2.4 ~ 27.1 months). One patient had severe abdominal and chest pain with prolonged hospitalization, and another patient had symptomatic radiation pneumonitis.

Conclusion: Radioembolization with curative intent can be performed with acceptable toxicity in patients with HCC fed by the IPA.